Electrical apparatus



April 26 1927. 1,626,182

J. G. CAMPBELL ELECTRICAL APPARATUS I Filed Feb. 24, 1923 2 Sheets-Sheet1 L7Zmw 5. CAMPBELL,

April 2651927. 1 7 1,626,182

' J. G. CAMPBELL ELECTRICAL APPARATUS Fild Feb. 124, 1923 2 sheets-sheet2 fizzrezz' Ur Q Jams: 5, CAMPBEL L 15 HZ70 111 2 E g Patented Apr. 26,19 27.

UNITED STATES PATIENT, ounce.

JOHN" G. CAMPBELL, OF DAYTON, OHIO, ASSIGNOR TO DELCO-LIGHT COMPANY, OFDAYTON, OHIO, ACORPORATION OF DELAWARE.

ELECTRICAL APPARATUS.

Application filed February 24, 1923. Serial No. 621,093.

I Thisv invention relates to alternating current motors, and moreparticularly the type of motor which should. be brought up tosynchronous speed before the motor drives a'machme.

This invention has among its objects to;

provide improvedmeans connecting the rotor of the motor with a drivenshaft after git certain rotor speed has been obtained. Another. objectis: to' provide improved 1 means for rendering inoperative, after thev,inotor has been brought up to a certain speed, an auxiliary circuitwhich is used in starting the motor.

Other and further 1 objects and advantages of the present invention willbe apparent from the following description of a preferred form thereof,reference being made to the accompanying drawings. In the drawings: Fig.1 is longitudinal sectional view of amotor including the presentinvention together with 'a fragmentary sectional view of a machine framewith which the motor is associated; Fig.2 is a side elevation partly insection showing the motor clutch in disengaged position;

Fig. 3 is a view similar-to Fig. 2 showing the clutch in engagedposition; .,Fig.1 4 is a sectional view taken on the line 4 -4 of Fig.2; Fig. 5 is a sectional view taken on the line 5--5 of Fig. l; and Fig.6 is a wiring diagram of the electrical circuits of the motor.

This invention contemplates mounting the rotor ofthe motor loosely upona ortion of the operating shaft of a mac ine 50- which is shown at 21,for supporting a main or operating shaft 22 having-a portion'zoextending beyond the bearing 21 and out side of the machine frame. Theportion 23 supports a flywheel. 24, and ournalled 5 thereupon, is arotorsleeve 25 having bearmeans of screws 43 to a m'ountingplate 44, but

upon which the motor is preferably mount-- ing bushings 26 and acup-shaped outer end 27. Sleeve 25 supports the motor rotor 28 which isof the squirrel-cage type and revolves within a motor field comprising ashell 29 attached to the frame 20, laminated field poles 30 and fieldwindings 31 and 32. \Vindings 31 constitute the main windings ofthemotor field, and windings 32 constitute the auxiliary or starting fieldwindings which are used to bring the motor from its state of rest up tosynchronous speed. The frame 20 constitutes an end frame for the fieldframe 29, the exposed end of which is enclosed by a removable cover 33having ventilating openings 34.

'Within the cover 33 there is located a: switch bracket 35 attached toframe 29 by screws 36. Bracket 35 carries a non-conducting switch base37 upon which are, mounted two semi-cylindrical switch contacts 38 whichtogether present a cylindrical surface adapted to be connected togetherby weight members 39 pivoted at 40 upon a weight plate 41 which alongwith plate 42 is attachedby insulated from plate 44 by means ofnon-conducting washer 45 andbushings 46. Plate '44 is attached to thecup-shaped end 27 of sleeve 25 by means of screws 47. Each spring 48 isattached at one end to a weight member 39 and at the other to a-stud 49riveted to the plate 42. One of the switch contacts 38 is connected bywire 50 with one of the motor leads 51 (see Fig. 6) and the othercontact 38 is connected by wire 52 with the starting field .winding 32.The springs 48 hold the Weights 39 in contact with one or more, of thecontacts 38 so that the contacts 38 are connected together by means of acircuit through the weights 39 and the plate 41.

When the motor leads are connected with a source of alternating current,the squirrelcage rotor 28 will be brought from a state of rest tosynchronous speed with the aid of the auxiliary starting field 32. "Whena certain speed of the rotor f-has been reached, the

weights 39 will move'outwardly away from the contacts 38 and interruptthe auxiliary field circuit 32. The'motor may now be connected with themachine to be driven by it through the clutch mechanism which will nowbe described. f I

y The motor clutch comprises friction discs 1 ,60 and 62 of any suitableflexible'or other friction material secured upon opposite sides anaxially of a mounting the shaft 23 and is keyed thereto by means of key63. The members 60, 61, and 62 provide slidable friction member which tobe clamped between two friction surfaces, namely, the surface 64provided on the flange 65 of the sleeve 25 and constituting an end wallof the cup 27, and the surface 66 of a disc slidable with respect to thesleeve 25 and is driven thereby. Mountin plate 44 carries three studs 68upon which t e plate 67 is slidable axially. Plate 44 carries threepairs of studs 69 and 78 upon which are mounted blocks 70 provided withwedging surfaces 71 which are oblique to the axis of shaft 23. Oppositeto the surfaces 71, the slidable clutch disc 67 is faces 72 which areobliquely inclined with respect to the axis of shaft 23 and with re-Spect tothe wedging surfaces 71. In order is adapted to wedge surfaces71 and 72 apart, a ball 73 is located between each pair of surfaces 71:md 72. Each ball 73 is'r'etained in 'position .by a weight member 74pivoted upon a stud 68 and provided with loosely receiving the ball 73.Each weight 74 carries a stud 76 connected with a' spring 77 attachedat-the other end to a stud '78 riveted to the mounting plate 44.

" Obviously rotation. of the rotor 28-causes V the weights 74 to berotated, and above a and clutchcan be motor and may be disasembled fromthe be mounted upon certain. rotor speed centrifugal produced by therotating weights will overcome the spring 77 and will cause the weights74 to move outwardly.- Each ball 73 will move into the narrower portionof the space between the inclined wedging surfaces 71 and 72, causin bewedged away from the blocks in a direction to the left as viewed in Fig.-1. Plate 67 will therefore engage the friction disc 61 which isslidable alongprovided with wedging sur-- :1. hole for 67 which isaxially to the shaft 23 fora cons1 force a the clutch plate 67 to t disc62 and will cause the disc 60 to beforced" portions carried by the motorrotor sleeve en the'motor comes to" rest, the weight members 39 and 74.will return to theirv respective positions shown in .Figs. 4 and 5,allowin the friction discs 60 and 62 to run free 0 the driving clutchmembers 65 and67, and

By virtue "of the construction which has been described, the speedresponsive switch mounted at one end'of a motor without disturbing otherparts thereof: Consequentlythe' motor is adapted to a machine frame withthe machine frame serving as a closure for one end of the motor fieldframe, and the motor rotor can be mounted upon an end of the machinefoperating shaft which extends causing a circuit to be madebetween theswitch contacts38.

against the friction 64. In thish manner the driven portion ,of thefriction clutch will be clamped between two driving 5 sponsivexswitchfor controllin ment relative shaft; a speed through and overhangs aportion of the machine frame. Such a motor and machine assembly is shownin the copending application of Kettering and Buvinger, Serial No.

299,195, filed May 23, 191.9, which discloses a motor driven pump. In amotor and machine unit of this type, the bearings of bracket 35 carryingwith it the contacts 38.

Then screws 47 are'removed and mounting plate 44 removed, thereb rembvinboth sets of weightelements. he clutch ocated withinthe cup 27 is nowexposed. -By removing nut 80, threaded on the end of shaft 23, theclutch elements '61 and 67 can be removed, and then with it the rotor28. 7

Since the sleeve 25 turns with to the shaft 23 only during the startingperiod of the motor, the bushings 26 are provided with grooves '26 forother non-fluid lubricant; and'one grcasi of; these bushings 26 willsupply lubrication While the! form of mechanism herein shown anddescribed constitutes a preferred embodiment of one form. to beunderstood that other forms mi ht be adopted and various changes and aternations made in the ShaPe, S1'Z6, and proportion of the elementstherein without departing from the spirit and scope of the inven- 1011.

' What is claimedis as follows:

1. In an electric motor, the combination with a motor frame including abearing, a shaft journalled in said bearing and overanging the bearing,on the overhanging portion of the shaft and rotatable with respect tothe shaft; 21. speed responsive clutch actuated by the rotor to connectthe rotor and shaft; a speed recuit; and meanssu cent the free end 0elements-of the clutch and switch.

-2.'"In an electric motor, the combination with a shaft anda rotormounted for moveto the shaft; a speed responported by t e rotoradjareceiving grease or erable period.

a motor cirthe sleeve 25 carrying of invention, it is and a rotormounted the sh'aft' for suppo ting sive clutch for connecting thc rotorand responsive switch for control- 1mg a motor circuit, said clutch andswitch each having centrifugall -operated elements disposed at one endof t e shaft, and means supportedby the rotor adjacent said end of theshaft for supporting said elements of the clutch and switch.

3. In an electric motor, the combination with a shaft and a rotormountedfor movement relative to the shaftya speed responsive ,clutch forconnecting the rotor and shaft; a speed responsive switch forcontrolling a motor circuit, said clutch and switch each havingspeed-responsive elements disposed adjacent one end of the shaft; and acommon means connected with and located adjacent said end of the rotorfor supporting said speed responsive elements of the clutch and switch.

4. In an electric motor,'the combination with a shaft and a rotormounted for movement relative to the shaft; a speed res onsive clutchfor connecting the rotor an the shaft; a speed responsive switch forcontrolling a motor circuit; and a mounted plate connected with therotor for supporting on one side thereof the centrifugal elements of theswitch, and, on the other side thereof,

the centrifugal elements of the clutch.

5. In an electric motor, the combination with a shaft and "a rotormounted for movement relative to 'thevshaft; a speed responsive clutchfor connectin the rotor and shaft, and including a weig t elementpivotally mounted to swing transverse to the shaft; a speedjresponsiveswitch for controlling a motor circuit and including a, weight elementpivotally mounted to swi transverse to the shaft {ands plate connect eigwith the rotor for supporting said weights on opposite sides thereof.

In testimony whereof; I hereto afiix my signature.

. JOHN eomennni

